ABO blood group predictions are brand new, and still under development. We're rolling it out to you so we can see how it performs on real data. All conclusions are still greatly limited by the general lack of phased data, the lack of genotyping at all of the necessary snps, and other factors.
best guess:rs8176719(D;D) rs8176746(C;C) rs8176747(C;C)rs8176719 (D;D) indicates you are type-O